walkmod-dead-code-cleaner-plugin

This is a walkmod plugin to remove unused declarations (imports, variables and private fields, methods and types) in Java source files. It applies the clean procedure in cascade. For example, if a unused method uses some types that are just used in this method, the imports related to these types are also removed.

Example

Let’s see an example. Take a look to this code. There is a private method called hello that is never referenced and also a variable in the goodBye method that also is never used.

package example;

import java.util.*;

public class Foo{
  private void hello(File file){
    ...
  }
  public void goodBye(){
    String s="bye";
    System.out.println("bye");
  }
}

What this plugins generates is the following modified code:

package example;

public class Foo{
  public void goodBye(){
    System.out.println("bye");
  }
}

Usage

Check that your walkmod version is at least 2.0.

1. Add the walkmod-maven-plugin into your walkmod.xml as a configuration provider. This plugin will interpret your classpath accoding your pom.xml and will build your project to make the application classpath available for walkmod.

2. Add the transformation dead-code-cleaner into your walkmod.xml.

<!DOCTYPE walkmod PUBLIC "-//WALKMOD//DTD" "http://www.walkmod.com/dtd/walkmod-1.1.dtd">
<walkmod>
    <conf-providers>
        <conf-provider type="maven"/>
    </conf-providers>
    <chain name="default">
        <transformation type="dead-code-cleaner"/>
    </chain>
</walkmod>

You can apply walkmod-dead-code-cleaner-plugin via walkmod.

$ walkmod apply

Or, you can also check which would be the modified classes typing:

$ walkmod check

Optionally, the plugin allows to select which elements are candidates to remove: private types, private methods, private fields, variables or imports:

	 <transformation type="dead-code-cleaner">
	 	<param name="removeUnusedImports">true</param>
	 	<param name="removeUnusedVariables">true</param>
	 	<param name="removeUnusedClasses">true</param>
	 	<param name="removeUnusedInterfaces">true</param>
	 	<param name="removeUnusedAnnotationTypes">true</param>
	 	<param name="removeUnusedEnumerations">true</param>
	 	<param name="removeUnusedMethods">true</param>
	 	<param name="removeUnusedFields">true</param>
	 </transformation>

Contributing

If you want to hack on this, fork it, improve it and send me a pull request.

To get started using it, just clone it and call mvn install.